This invention relates to the audio-visual field wherein sound is integrated with each still image to explain the contents of the image photographed or projected.
An objective of the invention is to provide transducer heads that need not be translated in order to record or reproduce sound.
Another objective is to provide more than one record or reproduce head associated with a driven record medium so that each head makes its own sound track independent of the tracks of other heads, but that the heads are sequentially switched after a predetermined period of operation of each head so that in effect the sound tracks made thereby are used in succession, consequently extending record or reproduce periods for each image photographed or displayed.
The prior art had the disadvantage of either having to transport or translate the head with respect to the record medium, or where the head is stationary, the amount of recording time practically possible without undue complexity of structure, is very limited.